CN103945606B - Doubleway output LED power drive circuit - Google Patents
Doubleway output LED power drive circuit Download PDFInfo
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- CN103945606B CN103945606B CN201410141212.1A CN201410141212A CN103945606B CN 103945606 B CN103945606 B CN 103945606B CN 201410141212 A CN201410141212 A CN 201410141212A CN 103945606 B CN103945606 B CN 103945606B
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Abstract
The invention discloses a kind of doubleway output LED power drive circuit, it comprises EMI filter circuit, rectification circuit, and governor circuit, the input of described EMI filter circuit is connected with civil power, its output is connected to governor circuit by rectification circuit, described governor circuit comprises main metal-oxide-semiconductor Q1, main metal-oxide-semiconductor Q2, export and control triode Q3, export and control triode Q4, LED 1, LED 2, and divider resistance R3, sampling resistor R4, sampling resistor R9, sampling resistor R10, controller U and the first dead time generator and the second dead time generator.Structure of the present invention is simple, can be cost-saving, and effectively can improve the efficiency of power supply, the indexs such as power factor.
Description
Technical field
Patent of the present invention relates to a kind of LED power drive circuit of two-way constant current output, refers in particular to a kind of low cost, high efficiency, and the constant current control power supply of High Power Factor drives.
Background technology
LED switch power supply is with efficiently, and environmental protection, the advantages such as backlight is good are just being used to each field, become the main flow of technical development, but LED field also exists a lot of problem now, and power factor is lower, and power-efficient is not high, high in cost of production.
Summary of the invention
The object of patent of the present invention is to provide a kind of structure simple, and efficiency is high, and power factor is high, can the LED power driver of current constant control of doubleway output.
For realizing above object, the technical scheme that this invention takes is:
A kind of doubleway output LED power drive circuit, it comprises EMI filter circuit, rectification circuit, and governor circuit, the input of described EMI filter circuit is connected with civil power, its output is connected to governor circuit by rectification circuit, described governor circuit comprises main metal-oxide-semiconductor Q1, main metal-oxide-semiconductor Q2, exports control triode Q3, exports control triode Q4, LED 1, LED 2 and divider resistance R3, sampling resistor R4, sampling resistor R9, sampling resistor R10, controller U and the first dead time generator and the second dead time generator; Wherein:
The grid of described main metal-oxide-semiconductor Q1 is connected to the output of rectification circuit, and its source electrode is connected to the emitter exporting and control triode Q3, and described output controls collector electrode ground connection after LED 1, sampling resistor R9 of triode Q3; The drain electrode of described main metal-oxide-semiconductor Q2 is connected between the source electrode of main metal-oxide-semiconductor Q1 and the emitter exporting control triode Q3, the source ground of described main metal-oxide-semiconductor Q2; The described emitter controlling triode Q4 that exports is connected between the source electrode of main metal-oxide-semiconductor Q1 and the emitter exporting control triode Q3, the described collector electrode ground connection after LED 2, sampling resistor R10 exporting control triode Q4, one end ground connection after described divider resistance R3, sampling resistor R4 series connection, the other end is connected between the source electrode of main metal-oxide-semiconductor Q1 and the emitter exporting control triode Q3;
The first sampling terminal A is provided with between described LED 1, sampling resistor R9, the second sampling terminal B is provided with between described LED 2, sampling resistor R10, the 3rd sampling terminal C is provided with between described divider resistance R3, sampling resistor R4, the voltage at described first sampling terminal A place is set to Va, the voltage at described second sampling terminal B place is set to Vb, and described 3rd sampling terminal C place voltage sets is Vi;
Described first sampling terminal A and the second sampling terminal B is connected to two inputs of controller U respectively, for Va, Vb are compared respectively with setting voltage value Vrefa, setting voltage value Vrefb, output enable signal outa-en and enable signal outb-en respectively, simultaneously, result relatively is also connected to output control triode Q3 by the second dead time generator output drive signal s3 and s4, described drive singal s3 and s4 and exports the base stage controlling triode Q4; Described 3rd sampling terminal C is connected to another input of controller U, for Vi is compared with peak voltage value Vpeak and peak voltage value Vvelly respectively, result is relatively by the first dead time generator output drive signal s1 and s2, and described drive singal s1 and s2 is connected to the grid of main metal-oxide-semiconductor Q1 and main metal-oxide-semiconductor Q2.
Described controller U is AVR single chip.
Described controller U comprises the first comparator, the second comparator, the 3rd comparator, the 4th comparator and rest-set flip-flop, finite state machine, zero-crossing detector, wherein, described 3rd sampling terminal C is connected with the positive input terminal of the second comparator respectively with the negative input end of the first comparator, is connected to the positive input terminal of the first comparator and the negative input end of the second comparator respectively for generation of the peak voltage source of peak voltage value Vvelly and peak voltage value Vpeak and peak voltage source, the output of described first comparator is connected to a wherein input of the first dead time generator by zero-crossing detector, the output of described second comparator is connected to the R end of rest-set flip-flop, the clock signal of controller U is connected to the S end of rest-set flip-flop, the Q end of rest-set flip-flop is connected to another input of the first dead time generator, and two outputs for producing first dead time generator of output drive signal s1 and s2 are respectively connected to the grid of main metal-oxide-semiconductor Q1 and the grid of main metal-oxide-semiconductor Q2 respectively, described first sampling terminal A and the second sampling terminal B is connected to the negative input end of the 3rd comparator and the 4th comparator respectively, the positive input terminal of the 3rd comparator and the 4th comparator is connected to respectively for generation of the fixed value voltage source Urefa of setting voltage value Vrefa and setting voltage value Vrefb and fixed value voltage source Urefb, the output of the 3rd comparator and the 4th comparator is connected to two inputs of finite state machine respectively, and produce one group of output signal in conjunction with the clock signal of another input of finite state machine, this group output signal is connected to two inputs of the second dead time generator respectively, two outputs for producing second dead time generator of output drive signal s3 and s4 are respectively connected to the base stage exporting and control triode Q3 and the base stage exporting control triode Q4 respectively.
Described governor circuit comprises one further and is connected to the source electrode of main metal-oxide-semiconductor Q1 and the filtering exported between the emitter controlling triode Q3 and phase compensating circuit, described filtering and phase compensating circuit comprise resistance R1, resistance R2, electric capacity C2 and inductance L, the resistance R1 after series connection and inductance L with connect after resistance R2 and inductance C2 be in parallel; The drain electrode of described main metal-oxide-semiconductor Q2 is connected between the source electrode of main metal-oxide-semiconductor Q1 and filtering and phase compensating circuit, described export the emitter controlling triode Q4 be connected to export and control triode Q3 between emitter and filtering and phase compensating circuit, the resistance R3 after series connection and one end of resistance R4 are connected between resistance R2 and inductance C2.
The described current value between emitter and filtering and phase compensating circuit controlling triode Q3 that exports is set to iL, the maximum of described iL is defined as imax, its minimum value is defined as imin, described peak voltage value Vpeak is the product of the resistance of imax and resistance R4, and described peak voltage value Vvelly is the product of the resistance of imin and resistance R4.
The LED 1 of series connection and the two ends of sampling resistor R9 also connect a RC filter circuit be composed in series by resistance R5 and electric capacity C3, and the LED 2 of series connection and the two ends of sampling resistor R10 also connect a 2nd RC filter circuit be composed in series by resistance R6 and electric capacity C4.
Described rectification circuit is full-wave rectification bridge.
The present invention compared with prior art, tool has the following advantages: in doubleway output conversion of the present invention, each road is all regulated its duty ratio by negative feedback type, realizes high power factor, thus improves the power factor of whole circuit, simultaneously, transformer configuration simplified, program control of the function before with circuit realiration being converted now also can realize required function, reduces the consumption on circuit, namely total consumption reduces, and raises the efficiency.And structure is simple, cost-saving.
Accompanying drawing explanation
Fig. 1 is the doubleway output LED power driving circuit principle figure of the embodiment of the present invention;
Fig. 2 is the generation schematic diagram of drive singal s1 and s2 of the present invention;
Fig. 3 is the generation schematic diagram of drive singal s3 and s4 of the present invention.
Embodiment
Below in conjunction with the drawings and specific embodiments, content of the present invention is described in further details.
Embodiment
Please refer to shown in Fig. 1, a kind of doubleway output LED power drive circuit, it comprises EMI filter circuit, rectification circuit, and governor circuit, the input of EMI filter circuit is connected with civil power, its output is connected to governor circuit by rectification circuit, governor circuit comprises main metal-oxide-semiconductor Q1, main metal-oxide-semiconductor Q2, export and control triode Q3, export and control triode Q4, LED 1, LED 2, and divider resistance R3, sampling resistor R4, sampling resistor R9, sampling resistor R10, controller U and the first dead time generator and the second dead time generator, wherein:
The grid of main metal-oxide-semiconductor Q1 is connected to the output of rectification circuit, and its source electrode is connected to the emitter exporting and control triode Q3, exports the collector electrode ground connection after LED 1, sampling resistor R9 controlling triode Q3; The drain electrode of main metal-oxide-semiconductor Q2 is connected between the source electrode of main metal-oxide-semiconductor Q1 and the emitter exporting control triode Q3, the source ground of main metal-oxide-semiconductor Q2; Exporting the emitter controlling triode Q4 is connected between the source electrode of main metal-oxide-semiconductor Q1 and the emitter exporting control triode Q3, export the collector electrode ground connection after LED 2, sampling resistor R10 controlling triode Q4, one end ground connection after divider resistance R3, sampling resistor R4 series connection, the other end is connected between the source electrode of main metal-oxide-semiconductor Q1 and the emitter exporting control triode Q3;
Sampling terminal A is provided with between LED 1, sampling resistor R9, sampling terminal B is provided with between LED 2, sampling resistor R10, sampling terminal C is provided with between divider resistance R3, sampling resistor R4, the voltage at sampling terminal A place is set to Va, the voltage at sampling terminal B place is set to Vb, and sampling terminal C place voltage sets is Vi;
Sampling terminal A and sampling terminal B is connected to two inputs of controller U respectively, for Va, Vb are compared respectively with setting voltage value Vrefa, setting voltage value Vrefb, coupling system clock systemclock, output enable signal outa-en and enable signal outb-en respectively, simultaneously, result relatively is also connected to output control triode Q3 by the second dead time generator output drive signal s3 and s4, drive singal s3 and s4 and exports the base stage controlling triode Q4; Sampling terminal C is connected to another input of controller U, for Vi is compared with peak voltage value Vpeak and peak voltage value Vvelly respectively, result is relatively by the first dead time generator output drive signal s1 and s2, and drive singal s1 and s2 is connected to the grid of main metal-oxide-semiconductor Q1 and main metal-oxide-semiconductor Q2.
In preferred embodiment of the present invention, rectifier bridge adopts full-wave rectifying circuit, and controller U adopts AVR single chip.
Governor circuit also comprises one and is connected to the source electrode of main metal-oxide-semiconductor Q1 and the filtering exported between the emitter controlling triode Q3 and phase compensating circuit, filtering and phase compensating circuit comprise resistance R1, resistance R2, electric capacity C2 and inductance L, resistance R1 after series connection and inductance L with connect after resistance R2 and inductance C2 be in parallel, wherein, filtering is again carried out with the direct current signal that inductance L is used for rectifier bridge exports, resistance R1 plays metering function, and the resistance R2 after series connection and inductance C2 plays effect of phase compensation; The drain electrode of main metal-oxide-semiconductor Q2 is connected between the source electrode of main metal-oxide-semiconductor Q1 and filtering and phase compensating circuit, export the emitter controlling triode Q4 be connected to export and control triode Q3 between emitter and filtering and phase compensating circuit, the resistance R3 after series connection and one end of resistance R4 are connected between resistance R2 and inductance C2.
Export the current value between emitter and filtering and phase compensating circuit controlling triode Q3 and be set to iL, the maximum of iL is defined as imax, its minimum value is defined as imin, peak voltage value Vpeak is the product of the resistance of imax and resistance R4, and peak voltage value Vvelly is the product of the resistance of imin and resistance R4.
The generation principle of drive singal s1 and s2 as shown in Figure 2, controller U comprises comparator A1, comparator A2, rest-set flip-flop and zero-crossing detector, sampling terminal C is connected with the positive input terminal of the second comparator respectively with the negative input end of the first comparator, the positive input terminal of comparator A1 and the negative input end of comparator A2 is connected to respectively for generation of the peak voltage source of peak voltage value Vvelly and peak voltage value Vpeak and peak voltage source (the peak voltage value Vpeak obtained by above-mentioned calculating and peak voltage value Vvelly simulates respectively by peak voltage source and peak voltage source), Vi is compared with peak voltage value Vpeak and peak voltage value Vvelly respectively, the output of comparator A1 is connected to the drive singal s2 of main metal-oxide-semiconductor Q2 grid by zero-crossing detector by carrying out acquisition after amplification process through an amplifier after the first dead time generator, the output of comparator A2 is connected to the R end of rest-set flip-flop, the clock signal systemclock of controller U is connected to the S end of rest-set flip-flop, the output Q of rest-set flip-flop holds and after an amplifier carries out amplifying process, obtains the drive singal s1 being connected to main metal-oxide-semiconductor Q1 grid by the first dead time generator, drive singal s1 and s2 produced by the first dead time generator can not be in open mode simultaneously.
The generation principle of drive singal s3 and s4 as shown in Figure 3, controller U comprises comparator A3, comparator A4 and finite state machine, sampling terminal A and sampling terminal B is connected to the negative input end of comparator A3 and comparator A4 respectively, the positive input terminal of comparator A3 and comparator A4 is connected to respectively for generation of the fixed value voltage source Urefa of setting voltage value Vrefa and setting voltage value Vrefb and fixed value voltage source Urefb, the output (be respectively and export challenge quantity outa-req and outb-req) of comparator A3 and comparator A4 is connected to two inputs of finite state machine respectively, and produce one group of enable signal and one group of output signal in conjunction with the clock signal systemclock of another input of finite state machine, be defined as enable signal outa-en and enable signal outb-en respectively and exported by finite state machine, one group of output signal is connected to two inputs of the second dead time generator respectively, also carry out producing drive singal s3 and s4 after amplification process through corresponding amplifier respectively by the second dead time generator, this drive singal s3 and s4 is connected to the base stage exporting and control triode Q3 and the base stage exporting control triode Q4, the possibility producing cross jamming between drive singal s3 and s4 is avoided by the second dead time generator.
In addition, series connection LED 1 and sampling resistor R9 two ends and connect a RC filter circuit be composed in series by resistance R5 and electric capacity C3, series connection LED 2 and sampling resistor R10 two ends and connect a RC filter circuit be composed in series by resistance R6 and electric capacity C4, further filtering is carried out to drive circuit, and then improve the life-span of LED.
Although the present invention is described by specific embodiment, it will be appreciated by those skilled in the art that, without departing from the present invention, various conversion can also be carried out and be equal to substituting to the present invention.In addition, for particular condition or application, various amendment can be made to the present invention, and not depart from the scope of the present invention.Therefore, the present invention is not limited to disclosed specific embodiment, and should comprise the whole execution modes fallen within the scope of the claims in the present invention.
Claims (7)
1. a doubleway output LED power drive circuit, it comprises EMI filter circuit, rectification circuit, and governor circuit, the input of described EMI filter circuit is connected with civil power, its output is connected to governor circuit by rectification circuit, it is characterized in that, described governor circuit comprises main metal-oxide-semiconductor Q1, main metal-oxide-semiconductor Q2, export and control triode Q3, export and control triode Q4, LED 1, LED 2, and divider resistance R3, sampling resistor R4, sampling resistor R9, sampling resistor R10, controller U and the first dead time generator and the second dead time generator, wherein:
The grid of described main metal-oxide-semiconductor Q1 is connected to the output of rectification circuit, and its source electrode is connected to the emitter exporting and control triode Q3, and described output controls collector electrode ground connection after LED 1, sampling resistor R9 of triode Q3; The drain electrode of described main metal-oxide-semiconductor Q2 is connected between the source electrode of main metal-oxide-semiconductor Q1 and the emitter exporting control triode Q3, the source ground of described main metal-oxide-semiconductor Q2; The described emitter controlling triode Q4 that exports is connected between the source electrode of main metal-oxide-semiconductor Q1 and the emitter exporting control triode Q3, the described collector electrode ground connection after LED 2, sampling resistor R10 exporting control triode Q4, one end ground connection after described divider resistance R3, sampling resistor R4 series connection, the other end is connected between the source electrode of main metal-oxide-semiconductor Q1 and the emitter exporting control triode Q3;
The first sampling terminal A is provided with between described LED 1, sampling resistor R9, the second sampling terminal B is provided with between described LED 2, sampling resistor R10, the 3rd sampling terminal C is provided with between described divider resistance R3, sampling resistor R4, the voltage at described first sampling terminal A place is set to Va, the voltage at described second sampling terminal B place is set to Vb, and described 3rd sampling terminal C place voltage sets is Vi;
Described first sampling terminal A and the second sampling terminal B is connected to two inputs of controller U respectively, for Va, Vb are compared respectively with setting voltage value Vrefa, setting voltage value Vrefb, output enable signal outa-en and enable signal outb-en respectively, simultaneously, result relatively is also connected to output control triode Q3 by the second dead time generator output drive signal s3 and s4, described drive singal s3 and s4 and exports the base stage controlling triode Q4; Described 3rd sampling terminal C is connected to another input of controller U, for Vi is compared with peak voltage value Vpeak and peak voltage value Vvelly respectively, result is relatively by the first dead time generator output drive signal s1 and s2, and described drive singal s1 and s2 is connected to the grid of main metal-oxide-semiconductor Q1 and main metal-oxide-semiconductor Q2; Drive singal s1 and s2 produced by the first dead time generator can not be in open mode simultaneously.
2. doubleway output LED power drive circuit according to claim 1, is characterized in that, described controller U is AVR single chip.
3. doubleway output LED power drive circuit according to claim 1 and 2, it is characterized in that, described controller U comprises the first comparator, second comparator, 3rd comparator, 4th comparator and rest-set flip-flop, finite state machine, zero-crossing detector, wherein, described 3rd sampling terminal C is connected with the positive input terminal of the second comparator respectively with the negative input end of the first comparator, the positive input terminal of the first comparator and the negative input end of the second comparator is connected to respectively for generation of the peak voltage source of peak voltage value Vvelly and peak voltage value Vpeak and peak voltage source, the output of described first comparator is connected to a wherein input of the first dead time generator by zero-crossing detector, the output of described second comparator is connected to the R end of rest-set flip-flop, the clock signal of controller U is connected to the S end of rest-set flip-flop, the Q end of rest-set flip-flop is connected to another input of the first dead time generator, and two outputs for producing first dead time generator of output drive signal s1 and s2 are respectively connected to the grid of main metal-oxide-semiconductor Q1 and the grid of main metal-oxide-semiconductor Q2 respectively, described first sampling terminal A and the second sampling terminal B is connected to the negative input end of the 3rd comparator and the 4th comparator respectively, the positive input terminal of the 3rd comparator and the 4th comparator is connected to respectively for generation of the fixed value voltage source Urefa of setting voltage value Vrefa and setting voltage value Vrefb and fixed value voltage source Urefb, the output of the 3rd comparator and the 4th comparator is connected to two inputs of finite state machine respectively, and produce one group of output signal in conjunction with the clock signal of another input of finite state machine, this group output signal is connected to two inputs of the second dead time generator respectively, two outputs for producing second dead time generator of output drive signal s3 and s4 are respectively connected to the base stage exporting and control triode Q3 and the base stage exporting control triode Q4 respectively.
4. doubleway output LED power drive circuit according to claim 3, it is characterized in that, described governor circuit comprises one further and is connected to the source electrode of main metal-oxide-semiconductor Q1 and the filtering exported between the emitter controlling triode Q3 and phase compensating circuit, described filtering and phase compensating circuit comprise resistance R1, resistance R2, electric capacity C2 and inductance L, the resistance R1 after series connection and inductance L with connect after resistance R2 and inductance C2 be in parallel; The drain electrode of described main metal-oxide-semiconductor Q2 is connected between the source electrode of main metal-oxide-semiconductor Q1 and filtering and phase compensating circuit, described export the emitter controlling triode Q4 be connected to export and control triode Q3 between emitter and filtering and phase compensating circuit, the resistance R3 after series connection and one end of resistance R4 are connected between resistance R2 and inductance C2.
5. doubleway output LED power drive circuit according to claim 4, it is characterized in that, the described current value between emitter and filtering and phase compensating circuit controlling triode Q3 that exports is set to iL, the maximum of described iL is defined as imax, its minimum value is defined as imin, described peak voltage value Vpeak is the product of the resistance of imax and resistance R4, and described peak voltage value Vvelly is the product of the resistance of imin and resistance R4.
6. doubleway output LED power drive circuit according to claim 1, it is characterized in that, the LED 1 of series connection and the two ends of sampling resistor R9 also connect a RC filter circuit be composed in series by resistance R5 and electric capacity C3, and the LED 2 of series connection and the two ends of sampling resistor R10 also connect a 2nd RC filter circuit be composed in series by resistance R6 and electric capacity C4.
7. doubleway output LED power drive circuit according to claim 1, is characterized in that, described rectification circuit is full-wave rectification bridge.
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| CN201410141212.1A CN103945606B (en) | 2014-04-09 | 2014-04-09 | Doubleway output LED power drive circuit |
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| CN201410141212.1A CN103945606B (en) | 2014-04-09 | 2014-04-09 | Doubleway output LED power drive circuit |
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| CN103945606B true CN103945606B (en) | 2016-01-13 |
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| CN102497092A (en) * | 2011-12-09 | 2012-06-13 | 顾选祥 | Zero current turning-on and zero current cutoff synchronous rectification control circuit |
| CN203014660U (en) * | 2012-12-07 | 2013-06-19 | 哈尔滨九洲电气股份有限公司 | Double-channel output IGBT driving module and circuit board thereof |
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2014
- 2014-04-09 CN CN201410141212.1A patent/CN103945606B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6864644B2 (en) * | 2002-11-14 | 2005-03-08 | Fyre Storm, Inc. | Method of tuning a circuit for energizing a cold cathode fluorescent lamp |
| CN101674001A (en) * | 2008-09-08 | 2010-03-17 | 德昌电机(深圳)有限公司 | Bridge driving circuit with blind area control |
| CN102055357A (en) * | 2009-10-27 | 2011-05-11 | 聚辰半导体(上海)有限公司 | Switch power supply controller circuit and switch power supply system |
| CN102497092A (en) * | 2011-12-09 | 2012-06-13 | 顾选祥 | Zero current turning-on and zero current cutoff synchronous rectification control circuit |
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